It never needs replacing just remove the filter occasionally, give it a good vacuuming, and replace it back into the unit. It also includes a washable pre filter that captures larger particles. An electronic filter clean indicator illuminates to remind you when to clean the filters.
The purifier changes the air in the room up to every 12 minutes with its powerful fan. For extra air freshening, it also features an ionizer that releases negative ions into outgoing humidified air, and these negative ions attach themselves to very small airborne particles to form larger particles that are then more readily captured by the filter system.
Other features include 3 air cleaning levels, a manual control dial, independent control for the ionizer, and antimicrobial treated filter that helps prevent mold growth. It measures 7 x 9 x 28 inches and has a 5 year limited warranty.